「Anime x Reader One Shots」

The Worst Mistake (Nishiki Nishio x Yandere!Reader)

"I can't anymore."

It was only three words, but they crushed your heart the second they were uttered. It hurt just as much as it did the day Nishio started dating Kimi. He was your everything, but he shattered your heart into a million pieces on that dreadful day. You couldn't understand why he was so attracted to her. She was plain, she was boring, she was human. How could he choose someone as weak as her over you?

You refused to let her keep you away from Nishio. Despite what he wanted, you still continued to flirt with him in hopes of getting closer to him. Day by day, he'd harshly turn down your efforts, but that didn't deter you away from him. No, if anything, it made you even more desperate to win his love. You would make him love you no matter what it took.

After months of him continuously turning you down, you were almost surprised he finally accepted your offer. Nishio was never the best at hiding his emotions and it was evident something was wrong. A fight between him and Kimi no doubt, but you could hardly care. He had finally let you in and that was all that mattered to you.

That night was the best night of your life. This man you loved more than anyone in the world was suffering through such a heartbreak and he chose you to be with. You comforted him with your presence, kind words, but most importantly; your body. That night, you belonged to him and he belonged to you. You were able to explore every inch of his perfect body and you enjoyed every second of it. Pleasure was the only method you knew of to help someone and it worked wonders on him.

As you laid there on your bed with his arms wrapped around your naked body, you were at peace. You thought that he was finally yours; that you had finally succeeded to win him over. But once again, Kimi managed to steal him away from you. Their argument didn't last much longer than a day and as soon as they made up, Nishio abandoned you once again.

"I can't anymore," was what he said. "We can't do this, (Y/N)."

"You didn't seem to have a problem with it last night," you replied back bitterly.

A look of pain crossed his face. "Last night was a mistake. It was wrong of me to do that to her."

Anger flared up inside you. A mistake? The only mistake Nishio ever made was dating that damn human in the first place. She was the only mistake he made! His mistake you desperately wished you could erase for him.

"So, what? You're just going to have sex with me one night and completely forget about me the next day?" you asked angrily.

"It was wrong of me to do that to the both of you. But I love her."

'Love' was such a strong word, but even you could tell he meant it. That's what truly tipped you over the edge. As hard as you tried to contain your tears of pure sorrow, they slipped down your cheeks. In just seconds, you found yourself choking on loud sobs that left your whole body convulsing.

You hoped that he could at least pity you for all the pain he put you through, but he didn't even look at you. He walked right past you with his eyes diverted away from you. "You shouldn't try to contact me anymore," was the last thing he said before leaving.

As you sat on your bed sobbing, you wanted desperately to hate Nishio but no matter how hard you tried, you just couldn't. If anything, you pitied him. It wasn't his fault that he broke your heart. No, he was a victim just like yourself. He was unknowingly being manipulated by that human you despised so much and only you could see it. As much pain you were in, you couldn't just sit there and continue to watch Kimi ruin the man you loved so much. She was going to have to pay for her actions.

You waited until you knew Nishio was working at Anteiku before arriving at Kimi's apartment. It took time to track down where she lived, but it would all be worth it. After knocking on her door, a smile appeared on your face as she opened the door. Just looking at her made you want to scream in rage, but your smile replaced the anger in knowing you would feel so much better in only a few more minutes.

"Hello?" she greeted hesitantly after opening the door. After all, you were still a complete stranger to her.

"You must be Kimi!" you greeted in a false, cheerful tone. "I'm (Y/N), a friend of Nishiki. I just have a belonging of his that I wanted to return and he told me I could drop it off here."

A sigh of relief escaped her mouth and she shot you a friendly smile. "Oh, of course. Please come in."

As soon as she closed the door behind you, she started walking off towards the living room with her back completely turned towards you. You nearly laughed out loud. She was boring and naive. What was it exactly about her that made Nishio love her so much? It was a question you would never know the answer to.

"So how do you know Nishio?" she asked curiously. You never replied. Instead, you released your kagune and began to slowly approach her. Just as you were only feet behind her, she turned around to face you. In an instant, the friendly look on her face turned to one of pure fear. Her terrified scream was the last sound she ever made before your kagune pierced through her body, ending her pathetic life.

All you could do was laugh as you watched the life fade from her eyes. Mad, crazed laughter escaped your mouth when you realized you had finally done it. There was nothing keeping you away from Nishio now. He was all yours.

The door to the apartment suddenly swung open and in came a distracted-looking Nishio. "Hey, Kimi, I brought you back-"

He stopped talking mid-sentence when he finally noticed the scene before him. The first thing he saw was Kimi's mutilated body lying before him. Then his eyes landed on you. Blood covered nearly every inch of your body, but he knew well enough that it wasn't your own.

"What the hell did you do?!" he shouted in horror as he lunged towards his girlfriend's body in hope that she was still alive. He didn't even need to check her pulse to know she was dead. There was far too much blood; there was no chance of her being alive.

"There's no need to be upset, Nishi," you said quickly with a crazed look on your face. "After all, now there's nothing stopping us from being together."

Nothing could ever stop you.